Host phospholipid peroxidation fuels ExoU-dependent cell necrosis and supports Pseudomonas aeruginosa-driven pathology

Salimata Bagayoko, Stephen Adonai Leon-Icaza, Miriam Pinilla, Audrey Hessel, Karin Santoni, David Péricat, Pierre-Jean Bordignon, Flavie Moreau, Elif Eren, Aurélien Boyancé, Emmanuelle Naser, Lise Lefèvre, Céline Berrone, Nino Iakobachvili, Arnaud Metais, Yoann Rombouts, Geanncarlo Lugo-Villarino, Agnès Coste, Ina Attrée, Dara W. Frank, Hans Clevers, Peter J. Peters, Céline Cougoule, Rémi Planès, Etienne Meunier

Published: September 2021


Regulated cell necrosis supports immune and anti-infectious strategies of the body; however, dysregulation of these processes drives pathological organ damage. Pseudomonas aeruginosa expresses a phospholipase, ExoU that triggers pathological host cell necrosis through a poorly characterized pathway. Here, we investigated the molecular and cellular mechanisms of ExoU-mediated necrosis. We show that cellular peroxidised phospholipids enhance ExoU phospholipase activity, which drives necrosis of immune and non-immune cells. Conversely, both the endogenous lipid peroxidation regulator GPX4 and the pharmacological inhibition of lipid peroxidation delay ExoU-dependent cell necrosis and improve bacterial elimination in vitro and in vivo. Our findings also pertain to the ExoU-related phospholipase from the bacterial pathogen Burkholderia thailandensis, suggesting that exploitation of peroxidised phospholipids might be a conserved virulence mechanism among various microbial phospholipases. Overall, our results identify an original lipid peroxidation-based virulence mechanism as a strong contributor of microbial phospholipase-driven pathology.

Full Access Link: PLoS Pathogens